At the system level, we compare three THz-NOMA baselines: (1) distance-based clustering and power allocation [1]}, (2) exhaustive-search-based user clustering and power allocation that maximizes user fairness per beam, and (3) THz-OMA with frequency-division-multiple-access (FDMA). Each NOMA group is assigned 1 GHz; each OMA user is allocated 1 GHz. The channels are generated using the TeraMIMO channel simulator [2]}; four transmitting and receiving SAs; 64 antennas per SA; carrier frequency of \([300]{GHz}\) . Although the channel dimension is \(4 \times 4\) , this is still considered an UM-MIMO system as the transmitter and the receiver consist of 256 antenna elements each. We assume 20 or 50 users per cell. Since 12 beams are required to cover the cell, on average, 24 users should exist in a cell for allocating two users per NOMA beam.
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